So,
Zev/Xev. In episode 2 of season 1, Kai says he wants to spend the rest of his undead life with Zev. This affection seems to carry through the entire Zev phase. Then, Zev dies and we have Xev. And Kai becomes cranky, or more to the point borderline offended (if he was alive) by Xev’s attentions. After watching all the seasons back to back for 6 months (yep, I have no life), I have a couple theories.
#1- Perhaps it’s a cultural thing. Kai was visibly moved by Zev’s sacrifice to save him. Maybe by reconstituting her, that lessens her sacrifice. Trivializing it.
#2- Zev was born human, with cluster lizard grafted on. The new Xev contained some but not all of the DNA sequences of Zev, plus some cluster lizard, and some plant, and some astronauts from Potatahoe. Xev was not a true reproduction of Zev. Neither in likeness, personality, or soul. Kai could sense this on subatomic level. So, the one he cared for was still dead.

Can't you move this discussion to it's proper place?
It is a little daunting for us newbies when arriving at The Lexxverse. I have found a grey area as big as the Lexx after reviewing the rules and reading the forums. So it is easy for us to be confused, sorry. I, myself have also entered something for discussion in the " wrong place".